PEG-MGF

A PEGylated version of mechano growth factor, the E-domain end of an IGF-1 splice variant (IGF-1Ec) that muscle switches on after heavy loading or damage. The PEG chain is meant to keep it stable and in circulation longer. It is sold for research only.

Plain MGF is gone within minutes, so people inject it daily, right after training, near the muscle they want to target. PEG-MGF is designed to last longer and spread through the body, so protocols drop to 2 or 3 shots a week at any under-the-skin site. The trade-off guides mention: less local action.

Forum protocols use 200 to 400 mcg, 2 to 3 times a week, with beginners at 100 to 200 mcg. PeptIQ app users most often log 200 to 400 mcg per shot, with reports up to 600 mcg. Use the calculator to turn a dose into syringe units for your vial.

Most protocols inject after training, from within 30 minutes for shots under the skin to 4 to 8 hours for shots into the muscle. Some guides prefer rest days instead, to stay clear of the body's own MGF pulse after exercise. None of these timings has been tested.

Guides use 1, 2 or 3 mL of bacteriostatic water. At 2 mL the vial is 1 mg/mL, so 200 mcg is 20 units on a U-100 insulin syringe.

Nobody knows. A 2026 review of these peptides found no reported half-life for PEG-MGF. Guide figures run from several hours to about 1 day to about 5 days, and none cites a measurement. Plain MGF lasts minutes.

The evidence is split and all of it is preclinical. In 2002 cell work the MGF E-domain made myoblasts multiply, and E-domain peptide protected heart muscle after heart attacks in sheep and mice. In 2014, two drug-company labs tried to reproduce the muscle-cell effect with native and stabilized MGF peptide and found nothing at up to 500 ng/ml, which led them to question whether MGF has a physiological role at all.

None. ClinicalTrials.gov lists no PEG-MGF or MGF trial, a 2026 review found no peer-reviewed human study, and FDA says it has found no human exposure data by any route.

Faster recovery between sessions is the most common report. Muscle gains are described as modest and gradual over 6 to 10 weeks, people say it works better stacked with IGF-1 LR3 or GH, and many find little benefit from it alone. These are anecdotes, not trial results.

Injection-site irritation is the one people actually log. Guides also list occasional headache and nausea. FDA flags a possible immune reaction to the product, and guides add theoretical anti-PEG antibodies, low blood sugar and growth-promoting effects.

Forum tables run 8 to 16 weeks with about 4 weeks off. Most guides run 4 to 8 weeks, and community protocols 6 to 10.

Not always. A doping lab found that two black-market MGF products were an amidated MGF analogue, not human MGF. Another lab found MGF inside vials sold as follistatin 344. PEGylation also adds a manufacturing step that labels cannot show.

No. It is listed among bulk substances once in FDA's 503A Category 2 whose nominations were withdrawn, and FDA's summary notes no human exposure data. Plain MGF is in Category 3, nominated without adequate support.

Yes. WADA lists mechano growth factors under S2.3, banned in and out of competition.

It is the most common pairing in community reports, PEG-MGF for repair signalling and LR3 for direct IGF-1 receptor action. No study has tested the pair.